Some manufacturers publish numbers in catalogs and on their
websites. This data may be misleading or contain outright lies. In
over a year and a half of researching silencers and the performance levels they
achieve, I have been amazed at some of the information I have discovered on
various websites and printed material. While some manufacturers have
chosen the high road and won't put numbers out there, others continue to put out
data that is unrepeatable, inaccurate or misleading. With this sort of
fiction floating around for the public to see, its easy to be confused about
what it all means. Al Paulson dedicated an entire chapter in his book
(Silencer History and Performance Volume One) called DEBUNKING MYTHS, ARTICLES,
AND CLAIMS to address this very issue. Let me share some of today's
examples of these "Claims" with you.

AWC Systems Technology has placed ads in magazines stating of
their 50 caliber and 556/223 silencers: "SOUND - Eliminated" This is not
possible as no silencer can eliminate sound.*

Surefire claims they fired 1,500 rounds full automatic with an
M4 carbine and the silencer "was barely even marked" and "had absolutely
nothing wrong with it." No 556/223 silencer can handle that type of
punishment and come out unscathed.*

Ops Inc claimed for years on its website that a 556/223
silencer they produce (3rd Model) attenuates sound to 40dB 96 feet in front of
the weapon. This type of testing does not meet the recognized standard
of testing.*

Advanced Armament Corp. also know as "AAC" published in their
2008 product catalog that "anyone seeking independent verification of the dB
reduction figures need look no further than the independent website
Silencertests.com..." This so-called independent website is run by an
AAC employee and has been since early 2006.*

Published Numbers by Manufacturers

Seldom have I found results that were published by manufacturers
to be accurate or repeatable. In almost every case, only a number is given
with no additional data. This makes it impossible to trust or believe what
you read on manufacturers websites or in published catalogs. Often all you
see is "Suppression Level" or "Sound Reduction" and a number. These
numbers fail to disclose what weapon was used, what ammunition was used, what
was the length of the barrel, what the velocities were, weather conditions,
standard used, equipment used for metering, etc... While many companies
don't do these things intentionally, the silencer buying public may have
misconceptions about how quiet a particular silencer may be. Some
companies are worse than others about the numbers they publish. Here are
some examples:

Yankee Hills Machine Company only puts out numbers with no
other data. Independent tests on this site show the YHM Mite to meter
between 24 and 31dB whereas the company website shows 35-40dB. *

Advanced Armament Corp. (aka AAC) publishes data for all of
the silencers they sell. Independent tests on this site have shown some
of those numbers to be unobtainable. Here are specific examples:
In May of 2007 I tested the AAC Prodigy. The silencer averaged 28dB of
reduction. The AAC website showed the silencer to offer between 38 and
40dB. Later testing showed that the AAC Prodigy couldn't achieve these
levels wet (water usually makes a silencer CONSIDERABLY quieter). The
designer of the silencer later told me he didn't actually test for net sound
reduction, but rather assigned a number to it by shooting a Prodigy and a
Pilot and subtracting the difference between the Pilot (shown at 41dB) and the
Prodigy which showed 1-3dB that day. The AAC Evolution 9 silencer shows
to meter dry at 34dB of reduction on the 2006 AAC Website. The current
information put out by AAC shows that number to have changed to 33dB.
Independent testing on this website using multiple hosts with several types of
ammunition showed around 29dB of reduction. *

The numbers shown by manufacturers simply cannot be taken into
consideration when comparing silencers for sound reduction. Also keep in
mind that just because any given manufacturer may not publish reproducible net
reduction numbers, does not necessarily mean they produce a poor or inferior
product. The practice of showing favorable numbers on product literature
and websites has gone on for years nearly unchecked. One thing this site
will always do is produce numbers that you can expect to get when you buy a
silencer. Here are some points to remember when you look at claims and
numbers published on manufactures websites and elsewhere:

Where did the data come from? If it was produced by the
company, be skeptical. If the information includes competitors
silencers, be VERY skeptical.

Does the data show what weapon, ammunition type, barrel
length, etc.?

Has the data been verified by an independent source such as Al
Paulson, or this site?

Was the equipment used to obtain the results capable of
catching the peak of a suppressed shot?

Was the equipment calibrated? The meter, microphone and
calibrator need to all have test certificates showing they were in calibration
at the time the readings were taken.

Where were the results obtained? Rifle class silencers
cannot be tested on indoor ranges and produce believable, repeatable results.

Be careful when
you are research what silencer to buy. It could save you thousands of
dollars in the long run.